I absolutely love this product. The others I've had in the past never provided enough coverage and were incapable of keeping the cold air completely out. There was always a little air that would sneak into the fabric. Not the case with the North Face WindStopper Ear Gear - I have full protection. I had no problem with the sizing. I am an adult female with a small head, so I just automatically ordered the medium, hoping it would work, and it did. There is just enough tension in the fabric to keep it from moving around. The only drawback, and this is a small one, is that the blockage is so good, that you might have trouble hearing someone talking to you, as it also blocks a bit of noise. I usually have to raise it up slightly if I need to talk to someone so that I can hear them. However, sometimes it's just plain more important to keep your ears warm than it is to hear! I do wish The North Face made one for my kids!